Files
android_kernel_xiaomi_sm8450/tools/testing/selftests/bpf/verifier/bounds.c
John Fastabend 41f70fe064 bpf: Test_verifier, add alu32 bounds tracking tests
Its possible to have divergent ALU32 and ALU64 bounds when using JMP32
instructins and ALU64 arithmatic operations. Sometimes the clang will
even generate this code. Because the case is a bit tricky lets add
a specific test for it.

Here is  pseudocode asm version to illustrate the idea,

 1 r0 = 0xffffffff00000001;
 2 if w0 > 1 goto %l[fail];
 3 r0 += 1
 5 if w0 > 2 goto %l[fail]
 6 exit

The intent here is the verifier will fail the load if the 32bit bounds
are not tracked correctly through ALU64 op. Similarly we can check the
64bit bounds are correctly zero extended after ALU32 ops.

 1 r0 = 0xffffffff00000001;
 2 w0 += 1
 2 if r0 > 3 goto %l[fail];
 6 exit

The above will fail if we do not correctly zero extend 64bit bounds
after 32bit op.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/158560430155.10843.514209255758200922.stgit@john-Precision-5820-Tower
2020-03-30 15:00:31 -07:00

542 lines
17 KiB
C

{
"subtraction bounds (map value) variant 1",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 9),
BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
BPF_JMP_IMM(BPF_JGT, BPF_REG_1, 0xff, 7),
BPF_LDX_MEM(BPF_B, BPF_REG_3, BPF_REG_0, 1),
BPF_JMP_IMM(BPF_JGT, BPF_REG_3, 0xff, 5),
BPF_ALU64_REG(BPF_SUB, BPF_REG_1, BPF_REG_3),
BPF_ALU64_IMM(BPF_RSH, BPF_REG_1, 56),
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_0, 0),
BPF_EXIT_INSN(),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
.errstr = "R0 max value is outside of the array range",
.result = REJECT,
},
{
"subtraction bounds (map value) variant 2",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 8),
BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
BPF_JMP_IMM(BPF_JGT, BPF_REG_1, 0xff, 6),
BPF_LDX_MEM(BPF_B, BPF_REG_3, BPF_REG_0, 1),
BPF_JMP_IMM(BPF_JGT, BPF_REG_3, 0xff, 4),
BPF_ALU64_REG(BPF_SUB, BPF_REG_1, BPF_REG_3),
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_0, 0),
BPF_EXIT_INSN(),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
.errstr = "R0 min value is negative, either use unsigned index or do a if (index >=0) check.",
.errstr_unpriv = "R1 has unknown scalar with mixed signed bounds",
.result = REJECT,
},
{
"check subtraction on pointers for unpriv",
.insns = {
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_LD_MAP_FD(BPF_REG_ARG1, 0),
BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_FP),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_ARG2, -8),
BPF_ST_MEM(BPF_DW, BPF_REG_ARG2, 0, 9),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_MOV64_REG(BPF_REG_9, BPF_REG_FP),
BPF_ALU64_REG(BPF_SUB, BPF_REG_9, BPF_REG_0),
BPF_LD_MAP_FD(BPF_REG_ARG1, 0),
BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_FP),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_ARG2, -8),
BPF_ST_MEM(BPF_DW, BPF_REG_ARG2, 0, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
BPF_EXIT_INSN(),
BPF_STX_MEM(BPF_DW, BPF_REG_0, BPF_REG_9, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 1, 9 },
.result = ACCEPT,
.result_unpriv = REJECT,
.errstr_unpriv = "R9 pointer -= pointer prohibited",
},
{
"bounds check based on zero-extended MOV",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 4),
/* r2 = 0x0000'0000'ffff'ffff */
BPF_MOV32_IMM(BPF_REG_2, 0xffffffff),
/* r2 = 0 */
BPF_ALU64_IMM(BPF_RSH, BPF_REG_2, 32),
/* no-op */
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_2),
/* access at offset 0 */
BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_0, 0),
/* exit */
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
.result = ACCEPT
},
{
"bounds check based on sign-extended MOV. test1",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 4),
/* r2 = 0xffff'ffff'ffff'ffff */
BPF_MOV64_IMM(BPF_REG_2, 0xffffffff),
/* r2 = 0xffff'ffff */
BPF_ALU64_IMM(BPF_RSH, BPF_REG_2, 32),
/* r0 = <oob pointer> */
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_2),
/* access to OOB pointer */
BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_0, 0),
/* exit */
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
.errstr = "map_value pointer and 4294967295",
.result = REJECT
},
{
"bounds check based on sign-extended MOV. test2",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 4),
/* r2 = 0xffff'ffff'ffff'ffff */
BPF_MOV64_IMM(BPF_REG_2, 0xffffffff),
/* r2 = 0xfff'ffff */
BPF_ALU64_IMM(BPF_RSH, BPF_REG_2, 36),
/* r0 = <oob pointer> */
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_2),
/* access to OOB pointer */
BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_0, 0),
/* exit */
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
.errstr = "R0 min value is outside of the array range",
.result = REJECT
},
{
"bounds check based on reg_off + var_off + insn_off. test1",
.insns = {
BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1,
offsetof(struct __sk_buff, mark)),
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 4),
BPF_ALU64_IMM(BPF_AND, BPF_REG_6, 1),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_6, (1 << 29) - 1),
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_6),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, (1 << 29) - 1),
BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_0, 3),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 4 },
.errstr = "value_size=8 off=1073741825",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
"bounds check based on reg_off + var_off + insn_off. test2",
.insns = {
BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1,
offsetof(struct __sk_buff, mark)),
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 4),
BPF_ALU64_IMM(BPF_AND, BPF_REG_6, 1),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_6, (1 << 30) - 1),
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_6),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, (1 << 29) - 1),
BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_0, 3),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 4 },
.errstr = "value 1073741823",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
"bounds check after truncation of non-boundary-crossing range",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 9),
/* r1 = [0x00, 0xff] */
BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
BPF_MOV64_IMM(BPF_REG_2, 1),
/* r2 = 0x10'0000'0000 */
BPF_ALU64_IMM(BPF_LSH, BPF_REG_2, 36),
/* r1 = [0x10'0000'0000, 0x10'0000'00ff] */
BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_2),
/* r1 = [0x10'7fff'ffff, 0x10'8000'00fe] */
BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 0x7fffffff),
/* r1 = [0x00, 0xff] */
BPF_ALU32_IMM(BPF_SUB, BPF_REG_1, 0x7fffffff),
/* r1 = 0 */
BPF_ALU64_IMM(BPF_RSH, BPF_REG_1, 8),
/* no-op */
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
/* access at offset 0 */
BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_0, 0),
/* exit */
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
.result = ACCEPT
},
{
"bounds check after truncation of boundary-crossing range (1)",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 9),
/* r1 = [0x00, 0xff] */
BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 0xffffff80 >> 1),
/* r1 = [0xffff'ff80, 0x1'0000'007f] */
BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 0xffffff80 >> 1),
/* r1 = [0xffff'ff80, 0xffff'ffff] or
* [0x0000'0000, 0x0000'007f]
*/
BPF_ALU32_IMM(BPF_ADD, BPF_REG_1, 0),
BPF_ALU64_IMM(BPF_SUB, BPF_REG_1, 0xffffff80 >> 1),
/* r1 = [0x00, 0xff] or
* [0xffff'ffff'0000'0080, 0xffff'ffff'ffff'ffff]
*/
BPF_ALU64_IMM(BPF_SUB, BPF_REG_1, 0xffffff80 >> 1),
/* r1 = 0 or
* [0x00ff'ffff'ff00'0000, 0x00ff'ffff'ffff'ffff]
*/
BPF_ALU64_IMM(BPF_RSH, BPF_REG_1, 8),
/* error on OOB pointer computation */
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
/* exit */
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
/* not actually fully unbounded, but the bound is very high */
.errstr = "value 72057594021150720 makes map_value pointer be out of bounds",
.result = REJECT
},
{
"bounds check after truncation of boundary-crossing range (2)",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 9),
/* r1 = [0x00, 0xff] */
BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 0xffffff80 >> 1),
/* r1 = [0xffff'ff80, 0x1'0000'007f] */
BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 0xffffff80 >> 1),
/* r1 = [0xffff'ff80, 0xffff'ffff] or
* [0x0000'0000, 0x0000'007f]
* difference to previous test: truncation via MOV32
* instead of ALU32.
*/
BPF_MOV32_REG(BPF_REG_1, BPF_REG_1),
BPF_ALU64_IMM(BPF_SUB, BPF_REG_1, 0xffffff80 >> 1),
/* r1 = [0x00, 0xff] or
* [0xffff'ffff'0000'0080, 0xffff'ffff'ffff'ffff]
*/
BPF_ALU64_IMM(BPF_SUB, BPF_REG_1, 0xffffff80 >> 1),
/* r1 = 0 or
* [0x00ff'ffff'ff00'0000, 0x00ff'ffff'ffff'ffff]
*/
BPF_ALU64_IMM(BPF_RSH, BPF_REG_1, 8),
/* error on OOB pointer computation */
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
/* exit */
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
/* not actually fully unbounded, but the bound is very high */
.errstr = "value 72057594021150720 makes map_value pointer be out of bounds",
.result = REJECT
},
{
"bounds check after wrapping 32-bit addition",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 5),
/* r1 = 0x7fff'ffff */
BPF_MOV64_IMM(BPF_REG_1, 0x7fffffff),
/* r1 = 0xffff'fffe */
BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 0x7fffffff),
/* r1 = 0 */
BPF_ALU32_IMM(BPF_ADD, BPF_REG_1, 2),
/* no-op */
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
/* access at offset 0 */
BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_0, 0),
/* exit */
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
.result = ACCEPT
},
{
"bounds check after shift with oversized count operand",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 6),
BPF_MOV64_IMM(BPF_REG_2, 32),
BPF_MOV64_IMM(BPF_REG_1, 1),
/* r1 = (u32)1 << (u32)32 = ? */
BPF_ALU32_REG(BPF_LSH, BPF_REG_1, BPF_REG_2),
/* r1 = [0x0000, 0xffff] */
BPF_ALU64_IMM(BPF_AND, BPF_REG_1, 0xffff),
/* computes unknown pointer, potentially OOB */
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
/* potentially OOB access */
BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_0, 0),
/* exit */
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
.errstr = "R0 max value is outside of the array range",
.result = REJECT
},
{
"bounds check after right shift of maybe-negative number",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 6),
/* r1 = [0x00, 0xff] */
BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
/* r1 = [-0x01, 0xfe] */
BPF_ALU64_IMM(BPF_SUB, BPF_REG_1, 1),
/* r1 = 0 or 0xff'ffff'ffff'ffff */
BPF_ALU64_IMM(BPF_RSH, BPF_REG_1, 8),
/* r1 = 0 or 0xffff'ffff'ffff */
BPF_ALU64_IMM(BPF_RSH, BPF_REG_1, 8),
/* computes unknown pointer, potentially OOB */
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
/* potentially OOB access */
BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_0, 0),
/* exit */
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
.errstr = "R0 unbounded memory access",
.result = REJECT
},
{
"bounds check after 32-bit right shift with 64-bit input",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 6),
/* r1 = 2 */
BPF_MOV64_IMM(BPF_REG_1, 2),
/* r1 = 1<<32 */
BPF_ALU64_IMM(BPF_LSH, BPF_REG_1, 31),
/* r1 = 0 (NOT 2!) */
BPF_ALU32_IMM(BPF_RSH, BPF_REG_1, 31),
/* r1 = 0xffff'fffe (NOT 0!) */
BPF_ALU32_IMM(BPF_SUB, BPF_REG_1, 2),
/* error on computing OOB pointer */
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
/* exit */
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
.errstr = "math between map_value pointer and 4294967294 is not allowed",
.result = REJECT,
},
{
"bounds check map access with off+size signed 32bit overflow. test1",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
BPF_EXIT_INSN(),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 0x7ffffffe),
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, 0),
BPF_JMP_A(0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
.errstr = "map_value pointer and 2147483646",
.result = REJECT
},
{
"bounds check map access with off+size signed 32bit overflow. test2",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
BPF_EXIT_INSN(),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 0x1fffffff),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 0x1fffffff),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 0x1fffffff),
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, 0),
BPF_JMP_A(0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
.errstr = "pointer offset 1073741822",
.errstr_unpriv = "R0 pointer arithmetic of map value goes out of range",
.result = REJECT
},
{
"bounds check map access with off+size signed 32bit overflow. test3",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
BPF_EXIT_INSN(),
BPF_ALU64_IMM(BPF_SUB, BPF_REG_0, 0x1fffffff),
BPF_ALU64_IMM(BPF_SUB, BPF_REG_0, 0x1fffffff),
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, 2),
BPF_JMP_A(0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
.errstr = "pointer offset -1073741822",
.errstr_unpriv = "R0 pointer arithmetic of map value goes out of range",
.result = REJECT
},
{
"bounds check map access with off+size signed 32bit overflow. test4",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
BPF_EXIT_INSN(),
BPF_MOV64_IMM(BPF_REG_1, 1000000),
BPF_ALU64_IMM(BPF_MUL, BPF_REG_1, 1000000),
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, 2),
BPF_JMP_A(0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
.errstr = "map_value pointer and 1000000000000",
.result = REJECT
},
{
"bounds check mixed 32bit and 64bit arithmatic. test1",
.insns = {
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_MOV64_IMM(BPF_REG_1, -1),
BPF_ALU64_IMM(BPF_LSH, BPF_REG_1, 32),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 1),
/* r1 = 0xffffFFFF00000001 */
BPF_JMP32_IMM(BPF_JGT, BPF_REG_1, 1, 3),
/* check ALU64 op keeps 32bit bounds */
BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 1),
BPF_JMP32_IMM(BPF_JGT, BPF_REG_1, 2, 1),
BPF_JMP_A(1),
/* invalid ldx if bounds are lost above */
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, -1),
BPF_EXIT_INSN(),
},
.result = ACCEPT
},
{
"bounds check mixed 32bit and 64bit arithmatic. test2",
.insns = {
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_MOV64_IMM(BPF_REG_1, -1),
BPF_ALU64_IMM(BPF_LSH, BPF_REG_1, 32),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 1),
/* r1 = 0xffffFFFF00000001 */
BPF_MOV64_IMM(BPF_REG_2, 3),
/* r1 = 0x2 */
BPF_ALU32_IMM(BPF_ADD, BPF_REG_1, 1),
/* check ALU32 op zero extends 64bit bounds */
BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_2, 1),
BPF_JMP_A(1),
/* invalid ldx if bounds are lost above */
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, -1),
BPF_EXIT_INSN(),
},
.result = ACCEPT
},